This project is designed to explore the feasibility of using somatic cells to screen for chemically induced chromosomal abnormalities. Inclusive in this project is the study of the relative sensitivities to chemical mutagens of germ cells and lymphocytes. Adult males are exposed to known chemical mutagens. Following exposure testicular sections from treated males, cytological preparations from cultured lymphocytes and sperm from the vas and epididymis will be examined for the presence of chemically induced abnormalities.